In Fiction, Write about them as unusual; or give people what they expect.
Everybody expects unusual characteristics in their prominent fictional characters (protagonist, antagonist, mentors, sidekicks, minions, love interest, etc).
My protagonist almost always has some unusual mental or physical ability; much of the story is coming to grips with that. Think "Good Will Hunting", Luke Skywalker, even Han Solo. So it would not suspend disbelief if, say, the love interest of your MC is a white Iranian; and the novelty of that is mentioned, perhaps as part of the attraction. And perhaps other Iranians are prejudiced against whites.
Nobody demands strict historical accuracy in historical fiction; they know the characters and personal parts of the setting are made up, and often the prominent characters are "fish out of water", thinking thoughts ahead of their time, even with morals ahead of their time, (intentionally on the author's part so readers can relate to them better).
That said, if the truth ruins your story, tie it up, gag it and stuff it in a mental closet. Fiction is not the place to push uncomfortable truths; leave that to professors in classrooms or non-fiction end-notes, if a publisher will allow them.
Fiction is for entertainment. If you think something actually factual will break suspension of disbelief for more than, say, 15% of your audience, don't include it. That is what is meant by the advice, "Kill Your Darlings." Don't include something you personally love even when you are pretty sure it will diminish or break the reading reverie. When they say readers like surprises, they mean plot surprises within the reading reverie about character pasts, motives, or actions. In Star Wars, the double surprise of Vader saying "I am your father," immediately followed by Luke intentionally letting go to (apparently) fall to his death (but to be rescued). A lot of "Holy crap!" moments, not "How ridiculous..." moments.
For the type of things you are talking about, the only context in which those become interesting and cool is one in which the reader believes they are reading (hearing, seeing) something absolutely true that will not lie to them, a non-fiction book. A professor in an anthropology class. A documentary film. A scientific paper, or report of a discovery in Science News or New Scientist.
Only in fiction does a reader suspend a certain amount of disbelief, so only in fiction must you be careful not to break it. Typically the way this "contract" works is that the author will quickly reveal (in the first 5% to 15% of the story, aka first half of Act I), in strong hints or in full, all the crazy things needed in the story. If there is magic, it must be shown there. Not every possible kind of magic, but impressive magic.
If you have Caucasians in fifth century Iran, show them. If you have Byzantine forks, show them being used, five story buildings, show them being used.
However, I'd guess there is a 90% chance you don't need to show any of these things at all: You shouldn't include a risk of suspension of disbelief unless it is crucial to the plot of your story or to character development. (In most stories what is unique or highly unusual about prominent characters is necessary, they need to stand out in the reader's mind).
It is your responsibility to leave out any widespread divergence from what readers believe is the true history, whether that divergence is factual or not. The point here is not to educate but to entertain, and asking people to believe something they feel certain is untrue is not entertaining them.